False-twist frames and method for texturing synthetic filaments



May 14, 1968 CROUZET 3,382,656

FALSE-TWIST FRAMES AND METHOD FOR TEXTURING SYNTHETIC FILAMENTS Filed Jan. 5, 1966 INVENTOR.

HENRI CROUZET (gmk / ATTORNEY United States Patent 3,382,656 FALSE-TWIST FRAMES AND METHOD FOR TEXTURING SYNTHETIC FILAMENTS Henri Crouzet, Riorges, Loire, France, assignor t0 Moulinage et Retorderie de Chavanoz, Chavanoz,

Isere, France, a corporation of France Filed Jan. 3, 1966, Ser. No. 518,410 4 Claims. (Cl. 5734) ABSTRACT OF THE DISCLOSURE A false-twist apparatus for the crimping of a textile yarn including delivery means for advancing the yarn from supply to takeup and between the delivery means, twisting means and heat setting means for application of false twist and for heat setting twist within the yarn. The improvement comprises a heating tube having at least three lobes forming multiple parallel channels, each connected by a heat transfer diaphragm. One of the lobes contains a temperature probe, and at least two other of the lobes serve as passageways for individual filaments. Resistance electrical heating means are provided for heating filaments disposed within the lobes, the filaments being individually heated for setting the false twist applied by an individual spindle downstream of the tube.

It is known to texture synthetic filaments on falsetwist spinning frames, i.e., spinning frames comprising spindles which impart to the filaments a false twist which progresses backwards into a heating element, which set the false twist on subsequent cooling. This texturing meth od has been very greatly developed in recent years and the equipment required has at the same time undergone a considerable change.

In one of the systems employed in this field, the threads undergo the heating in contact with fixed convex metallic heating elements. Initially, hollow elements were provided through which there was circulated a fluid heated at a regulated constant temperature. Subsequently, electric heat was employed, also with appropriate adjustment. The device employed was first of all a bent metallic channel, called an umbrella rib, which constituted in itself the electric resistor heated by the Joule effect. This channel was later replaced by a bent metallic tube connected as before as an electric resistor. Tubes had the advantage that they were more readily thermally insulated. All the tubes were connected in series and were carefully calibrated to ensure a constant temperature from tube to tube.

For measuring the temperature and for adjusting it, at least one of the tubes of a spinning frame was free from filament and contained a temperature probe connected to monitoring and adjusting instruments.

The object of the present invention is to provide a heating tube for false-twist spinning frames having a crosssection comprising a number of lobes subdividing the tube into a number of coupled channels, one channel containing a resilient electric probe, while the other channels permit the passage of filaments to be heated. Each active channel forms part of an operating position with the other usual elements, i.e., notably a supply reel, delivery members, a false-twist spindle and a take-up reel.

The invention not only includes bent tubes directly electrically heated by resistance, but also straight tubes. The heating may also be indirect. In any case, the invention is in no way limited to the following embodiment, but covers any variant in the same spirit. The object is to provide a heating element comprising a number of parallel channels, one of which contains a temperature probe, while the others serve for the passage of filament, the

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probe being subjected to the same thermal conditions as the filaments.

In addition, the system has the advantage that it permits multiplication of the output of the spinning frames, which is obviously primarily determined by the number of channels for the passage of filament. With tubes having a cross-section comprising a plurality of lobes, particularly three lobes, the output is doubled for the same Working speed. Another advantage is that each working position may be effectively controlled in regard to the thermal conditions.

The embodiment will enable the invention, which is illustrated by the diagrammatic drawing on the accompanying sheet, to be more readily understood.

In FIGURE 1, there is illustrated an embodiment comprising a tube having a three-lobe or clover leaf crosssection. Such a tube may be obtained by passing a larger tube through an appropriate die by which the tube is deformed.

In FIGURE 1, the tube of the example, which is illustrated in section, comprises three channels 1, 2 and 3 connected by diaphragms 4, 5 and 6 created in the deformation of the initial tube. These diaphragms may be closed by complete clamping of the opposed partitions, but this is not essential. Each of the plurality of lobes or tubes may, of course, constitute separate tubes that are interconnected by a good heat conducting means, such as copper or alloy, or equivalent heat conducting metal means.

The channel 1 contains a temperature probe connected to monitoring and adjusting devices for checking the temperature of the channel 7 at each instant and maintainin g it between predetermined narrow limits.

The channels 2 and 3 contain filaments 8 and 9 which undergo the heating.

In the direct resistance heating of the tube, the temperature is the same throughout, subject to losses by radiation, which may differ slightly in the same channels, if the thermal insulation is not absolutely uniform.

Referring to FIGURE 2 of the drawing, the filaments 10 and 10 pass from the cones 11 and 11' through guide means 12 and 12 and then through parallel lobes 13 and 13, which in the form shown is curved so that the filaments contact the surfaces of the tubes as they are fed therethrough. In some instances, however, the tubes may be made straight instead of curved and the filaments be caused to contact the sides of the tubes by suitable guide means. The heating tubes that comprise lobes 13 and 13' are connected to tube 14 through heat transfer means 16 with terminals 15 which are connected to a suitable source of electric current for heating the tubes by resistance effect. Lobes 13 and 13 are preferably interconnected by a heat transfer means that is preferably made of the same metal as the lobes, so as to have the same resistance, and is preferably made from a metal known for its high resistance properties, for example, of nickel chrome alloy or metals or alloys of a lower resistance. The applied current is preferably low. The heater tubes 13 and 13 are interconnected by heat transfer means 16. The tubes may be thermally insulated at least in the areas where the tubes are not connected by enclosing them in a larger tube 17 and 17' which are cut away to allow the heat transfer means 16 to be joined to the heater tubes, and are lined by an insulating material, for example, vermiculite which fills the space between the inner wall of the large tubes and surfaces of the heater tubes or resistor tubes 13 and 13'. The ends of the large tube 17 are closed by disc 18 and 18, for example, by a plastic material with an orifice the size of the diameter of tube 13 and 13'.

The filaments after passing through the tubes 13 and 13 are fed through false twist spindles 9 and 18' which are rotated by simple means indicated as a belt 20 and is adapted to produce a twist in the filament which feeds back on the filament towards the heating tubes 13 and 13 until arrested by contact with the filaments with the surfaces of such tubes. The temperature of the tubes 13 and 13 is adapted to heat the filaments for setting the false twist. Finally, the filaments 1G and 10" pass through a guide 21 and 21' and are then Wound onto spools 22 and 22'. Therefore, by means of this invention at least two yarns and actually many more may be advanced through adjacent parallel lobes of a single tube, or through adjacent individual tubes that are interconnected by a suitable heat transfer means With a means located in an adjacent tube that is also connected by heat transfer means to each of the said other lobes or tubes for measuring and controlling temperature throughout the heater tube system.

The invention may comprise in addition the following elements singly or in any combination:

(a) The tubes may be heated by any means.

(b) Direct or indirect electric heating is employed.

(c) The tubes may be straight or bent.

(d) There is employed notably a bent tube directly heated by resistance and having a cross-section comprising three lobes, with optionally partitioned intermediate diaphragms.

Each of the individual yarns that are processed by the method and apparatus of this invention may be false twisted by individual spindles or by a single spindle that twists a number of yarns. In the second case, a special yarn guide means is needed so that the plurality of yarns are properly fed into the false-twist spindle.

Having thus described the invention,.wh at is claimed is:

1. In a false-twist apparatus for the crimping of a textile yarn including delivery means for advancing the yarn from supply to t-akeup and between said delivery means, twisting means and heat setting twist within the yarn, respectively, the improvement comprising a heating tube having at least three lobes forming multiple parallel channels, each connected by a heat transfer diaphragm, one of said lobes containing a temperature probe, and at least two other of said lobes serving as passageways for individual filaments, resistance electrical heating means for heating filaments disposed within said lobes, whereby the filaments are individually heated for setting the false twist applied by an individual spindle downstream of the tube.

2. The apparatus of claim 1 wherein the heater tube is arcua-te in shape.

3. The apparatus of claim 1 further characterized in that the tube is straight.

4. The apparatus of claim 1 wherein the heater tube is comprised of at least four lobes.

References Cited UNITED STATES PATENTS 2,803,108 8/1957 Stoddard et a1. 5734 XR 2,864,229 12/1958 Seem et a1. 57-34 2,869,312 1/1959 Van Dijk 57-34 2,891,375 6/1959 Van Damme et a1 57-34 3,289,400 12/1966 Scragg 57-34 FOREIGN PATENTS 824,942 12/ 1959 Great Britain.

FRANK J. COHEN, Primary Examiner.

W. H. SCHROEDER, Assistant Examiner. 

